sys/mips/atheros/ar71xx_wdog.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2009, Oleksandr Tymoshenko <gonzo@FreeBSD.org>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice unmodified, this list of conditions, and the following
  12  *    disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 /*
  31  * Watchdog driver for AR71xx
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include <sys/param.h>
  38 #include <sys/eventhandler.h>
  39 #include <sys/systm.h>
  40 #include <sys/watchdog.h>
  41 #include <sys/bus.h>
  42 #include <sys/kernel.h>
  43 #include <sys/module.h>
  44 #include <sys/sysctl.h>
  45
  46 #include <mips/atheros/ar71xxreg.h>
  47 #include <mips/atheros/ar71xx_cpudef.h>
  48
  49 struct ar71xx_wdog_softc {
  50         device_t dev;
  51         int armed;
  52         int reboot_from_watchdog;
  53         int debug;
  54 };
  55
  56 static void
  57 ar71xx_wdog_watchdog_fn(void *private, u_int cmd, int *error)
  58 {
  59         struct ar71xx_wdog_softc *sc = private;
  60         uint64_t timer_val;
  61
  62         cmd &= WD_INTERVAL;
  63         if (sc->debug)
  64                 device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: cmd: %x\n", cmd);
  65         if (cmd > 0) {
  66                 timer_val = (uint64_t)(1ULL << cmd) * ar71xx_ahb_freq() /
  67                     1000000000;
  68                 if (sc->debug)
  69                         device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: programming timer: %jx\n", (uintmax_t) timer_val);
  70                 /*
  71                  * Load timer with large enough value to prevent spurious
  72                  * reset
  73                  */
  74                 ATH_WRITE_REG(AR71XX_RST_WDOG_TIMER,
  75                     ar71xx_ahb_freq() * 10);
  76                 ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL,
  77                     RST_WDOG_ACTION_RESET);
  78                 ATH_WRITE_REG(AR71XX_RST_WDOG_TIMER,
  79                     (timer_val & 0xffffffff));
  80                 sc->armed = 1;
  81                 *error = 0;
  82         } else {
  83                 if (sc->debug)
  84                         device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: disarming\n");
  85                 if (sc->armed) {
  86                         ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL,
  87                             RST_WDOG_ACTION_NOACTION);
  88                         sc->armed = 0;
  89                 }
  90         }
  91 }
  92
  93 static int
  94 ar71xx_wdog_probe(device_t dev)
  95 {
  96
  97         device_set_desc(dev, "Atheros AR71XX watchdog timer");
  98         return (BUS_PROBE_NOWILDCARD);
  99 }
 100
 101 static void
 102 ar71xx_wdog_sysctl(device_t dev)
 103 {
 104         struct ar71xx_wdog_softc *sc = device_get_softc(dev);
 105
 106         struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->dev);
 107         struct sysctl_oid *tree = device_get_sysctl_tree(sc->dev);
 108
 109         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 110                 "debug", CTLFLAG_RW, &sc->debug, 0,
 111                 "enable watchdog debugging");
 112         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 113                 "armed", CTLFLAG_RD, &sc->armed, 0,
 114                 "whether the watchdog is armed");
 115         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 116                 "reboot_from_watchdog", CTLFLAG_RD, &sc->reboot_from_watchdog, 0,
 117                 "whether the system rebooted from the watchdog");
 118 }
 119
 120
 121 static int
 122 ar71xx_wdog_attach(device_t dev)
 123 {
 124         struct ar71xx_wdog_softc *sc = device_get_softc(dev);
 125
 126         /* Initialise */
 127         sc->reboot_from_watchdog = 0;
 128         sc->armed = 0;
 129         sc->debug = 0;
 130
 131         if (ATH_READ_REG(AR71XX_RST_WDOG_CONTROL) & RST_WDOG_LAST) {
 132                 device_printf (dev,
 133                     "Previous reset was due to watchdog timeout\n");
 134                 sc->reboot_from_watchdog = 1;
 135         }
 136
 137         ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL, RST_WDOG_ACTION_NOACTION);
 138
 139         sc->dev = dev;
 140         EVENTHANDLER_REGISTER(watchdog_list, ar71xx_wdog_watchdog_fn, sc, 0);
 141         ar71xx_wdog_sysctl(dev);
 142
 143         return (0);
 144 }
 145
 146 static device_method_t ar71xx_wdog_methods[] = {
 147         DEVMETHOD(device_probe, ar71xx_wdog_probe),
 148         DEVMETHOD(device_attach, ar71xx_wdog_attach),
 149         {0, 0},
 150 };
 151
 152 static driver_t ar71xx_wdog_driver = {
 153         "ar71xx_wdog",
 154         ar71xx_wdog_methods,
 155         sizeof(struct ar71xx_wdog_softc),
 156 };
 157 static devclass_t ar71xx_wdog_devclass;
 158
 159 DRIVER_MODULE(ar71xx_wdog, nexus, ar71xx_wdog_driver, ar71xx_wdog_devclass, 0, 0);